JPH05189758A - Magnetic disk and magnetic head and production thereof - Google Patents

Abstract

PURPOSE:To stabilize the floating and traveling of the magnetic head by forming the plural projections smaller than pattern projecting parts on the surface of the pattern projecting parts of the magnetic disk. CONSTITUTION:The pattern projecting parts 5 having air compressing parts heading toward the front side in the rotating direction of the magnetic disk 1 are provided on the surface, etc., of the disk 1 and further, the projections 6 smaller than the projecting parts 5 are provided on the surface of the projecting parts 5. A positive pressure region is generated in the surface part of the disk 1 by the air compressing parts of the pattern projecting parts 5 and the magnetic head 2 is rapidly floated at the time of starting the rotation of the disk according to such constitution. In addition, the head 2 comes into contact with the disk 1 via the small projections 6 and the attraction of the head 2 to the disk 1 does not arise. The floating and traveling of the magnetic head are thus stabilized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk capable of stabilizing the flying and running of a magnetic head, a magnetic head and a method for manufacturing them.

[0002]

2. Description of the Related Art In a disk-shaped magnetic disk used in a magnetic recording device of a computer, signals are written and read by a magnetic head.
This magnetic head contacts a magnetic disk surface when the magnetic disk is stopped, and a so-called CSS (contact start stop) that floats by the pressure of the airflow generated on the magnetic disk surface when the magnetic disk is rotated. The magnetic head is designed to write and read signals in a floating state.

Now, the stopped state of the magnetic head and the flying running state will be described in more detail. At the time of starting the magnetic disk, the magnetic head is in a state of being pressed against the surface of the magnetic disk by the spring pressure of the spring plate member supporting itself. When the magnetic disk starts rotating from this state, the magnetic head slides while being in contact with the rotating magnetic disk. Next, as the rotational speed of the magnetic disk increases, the lift force due to the air flow generated on the surface of the magnetic disk rises, and when this lift force overcomes the spring pressure on the magnetic head, the magnetic head gently floats above the surface of the magnetic disk. Then, it floats on the magnetic disk while maintaining the flying height determined by the shape of the magnetic head, the spring pressure, and the peripheral speed of the magnetic disk.

That is, the magnetic head rubs the surface of the magnetic disk from the start of rotation of the magnetic disk to the start of flying of the magnetic head while being restrained by spring pressure. For this reason, conventionally, the surface of the magnetic disk or the surface of the magnetic head facing the medium is abraded, and in some cases the frictional force rises abnormally, causing the surface of the magnetic disk to crash (crash), and the recorded contents of the magnetic disk can be read. It was sometimes gone. Further, when the frictional force between the magnetic head and the magnetic disk abnormally rises to a value equal to or greater than the rotational torque of the magnetic disk, the magnetic disk will no longer rotate, which may lead to failure of the magnetic recording device.

[0005]

In order to solve such a problem, conventionally, a slider of a magnetic head is provided with a rail portion for flying travel, or an inclined surface is formed at an end of the rail portion when flying. The magnetic head is constructed by adopting a structure in which the lift of the magnetic head is improved and the magnetic head can quickly fly.
Even if such a structure is adopted, the surface of the magnetic disk may still be destroyed. The surface of the magnetic head on the medium facing surface side is mirror-finished, and the surface of the magnetic disk is also mirror-finished.However, when parts of the mirror-finished surfaces come in contact with each other, the magnetic heads are attracted to each other. There is a problem that it sticks to the magnetic disk and becomes immobile, which leads to failure of the magnetic recording device as in the case described above.

On the other hand, the magnetic disk rotates at a constant speed, and the peripheral speed of the magnetic disk is different between the inner peripheral portion of the surface and the outer peripheral portion of the surface. Therefore, the magnitude of the generated airflow varies depending on the location of the magnetic disk. .. That is, the flying height of the magnetic head tends to be low at the inner peripheral portion of the magnetic disk surface and high at the outer peripheral portion of the surface. Here, the recording magnetic field of the magnetic head and the leakage magnetic field of the magnetic disk become smaller according to the distance from the magnetic disk. Therefore, it is inconvenient in terms of magnetic recording and reproduction that the flying height of the magnetic head varies between the inner surface side and the outer surface side of the magnetic disk.

Therefore, conventionally, in order to solve such a problem, the magnetic head is provided with an inclination called a skew angle so as to face the magnetic disk, and the center line of the magnetic head and the magnetic disk are provided on the inner peripheral portion of the surface of the magnetic disk. There is provided a magnetic head configured so that the relationship between the peripheral speed and the flying height is changed by matching the tangential directions of the above and shifting them toward the outer peripheral portion. However, the flying height of a normal magnetic head is 0.1 to 0.1.
It is about 3 μm, which is an extremely small value, and making the flying height of the magnetic head the same on the inner circumference side of the magnetic disk surface due to the skew angle requires high processing accuracy and obtains sufficient flying height stability. Is difficult.

For the purpose of solving the above problems, the applicant of the present application has filed a patent application for a magnetic disk and a magnetic head having a pattern having an air compression portion in Japanese Patent Application Laid-Open No. 3-317059. Therefore, the inventor of the present application further arrived at the present invention as a result of repeated studies on the magnetic disk and the magnetic head of the above-mentioned patent application in order to facilitate the floating of the magnetic head.

The present invention has been made in view of the above circumstances, and the magnetic head can be quickly levitated when the magnetic disk is rotated, and the flying height of the magnetic head can be stabilized. An object of the present invention is to provide a magnetic disk and a magnetic head that can reduce wear and a method for manufacturing them.

[0010]

In order to solve the above-mentioned problems, according to the present invention, in a magnetic disk in which information is read / written by a magnetic head and is rotationally driven, at least one of a front surface and a back surface of the magnetic disk is used. In addition, a plurality of pattern protrusions having an air compression portion facing the front side in the rotation direction of the magnetic disk are formed, and a plurality of protrusions smaller than the pattern protrusions are formed on the surface of the pattern protrusions.

In order to solve the above-mentioned problems, the invention according to claim 2 reads and writes information by a magnetic head,
A magnetic disk that is rotationally driven, wherein a plurality of pattern projections each having an air compression portion facing the front side in the rotation direction of the magnetic disk are formed on at least one of the front surface and the back surface of the magnetic disk, and the pattern projections are formed on the surface. In a method of manufacturing a magnetic disk having a plurality of protrusions smaller than a pattern protrusion, a first mask pattern is formed on a substrate of the magnetic disk, and the substrate is selectively etched along the first mask pattern. A part of the substrate is etched to form a pattern protrusion on the front surface or the back surface of the substrate, and a second mask pattern is further formed on the substrate on which the pattern protrusion is formed, and selection is performed along the second mask pattern. Specifically, a part of the pattern protrusion is etched to form a plurality of protrusions on the surface of the pattern protrusion.

In order to solve the above-mentioned problems, the invention according to claim 3 levitates and travels with respect to a rotating magnetic disk,
In a magnetic head that comes into contact with a magnetic disk in a stopped state, a pattern projection having an air compression portion facing the rear side in the rotation direction of the magnetic disk is formed on the surface of the magnetic head on the magnetic disk side. A plurality of protrusions smaller than the pattern protrusions are formed on the surface of the.

In order to solve the above-mentioned problems, the invention according to claim 4 levitates and travels with respect to a rotating magnetic disk,
A magnetic head that comes into contact with a magnetic disk in a stopped state, wherein a surface of the magnetic head on the magnetic disk side is provided with a pattern projection having an air compression section that faces the rear side in the rotation direction of the magnetic disk, In a method of manufacturing a magnetic head having a plurality of protrusions smaller than the pattern protrusion on the surface of the pattern protrusion, a coating layer is formed on the surface of the magnetic head on the magnetic disk side, and a first layer is formed on the coating layer. And forming a pattern projection on the surface of the coating layer by selectively etching a part of the coating layer along the first mask pattern. A second mask pattern is further formed on the surface of the pattern protrusion, and a part of the pattern protrusion is selectively etched along the second mask pattern to form a plurality of protrusions on the surface of the pattern protrusion. It is.

[0014]

Since a plurality of pattern protrusions each having an air compressing portion facing the front side in the rotating direction of the magnetic disk are formed on the surface of the magnetic disk, the air compressing portion of each pattern protruding portion acts on the magnetic disk when the magnetic disk rotates. A positive pressure area is generated on the disk surface portion, and an air flow resulting from this is generated. Then, this air flow acts on the magnetic head to quickly levitate the magnetic head. An air flow is generated by rotation even in a normal magnetic disk having no pattern protrusion, but in a magnetic disk having a pattern protrusion,
The positive pressure generated by the air compression effect of the pattern protrusions at the start of rotation can immediately generate a strong air flow, so that the magnetic head floats faster than before. Therefore, at the start of rotation of the magnetic disk, the time required for the magnetic head to contact and rub the magnetic disk is shortened, and the risk of damage to the magnetic disk is reduced.

When the magnetic head is in contact with the magnetic disk when the magnetic disk is stopped, the magnetic head comes into contact with the magnetic disk through the projections on a plurality of pattern projections formed on the magnetic disk. To do. Then, the conventional contact between the mirror surfaces is eliminated, and the contact area is reduced, so that the phenomenon that the magnetic head is attracted to the magnetic disk does not occur. Therefore, the failure of the magnetic recording device that has conventionally occurred due to the attraction phenomenon of the magnetic head does not occur.

Furthermore, since the pattern projection having the air compression portion facing the rear side in the rotation direction of the magnetic disk is formed on the bottom surface of the magnetic head on the magnetic disk side, the air compression of the pattern projection is performed when the magnetic disk is rotated. The positive pressure generated by the action of the section is generated on the bottom side of the magnetic head. Therefore, this positive pressure causes the magnetic head to fly faster than the conventional magnetic head. Therefore, at the start of rotation of the magnetic disk, the time required for the magnetic head to contact and rub the magnetic disk is shortened, and the risk of damage to the magnetic disk is reduced.
When the magnetic head is in contact with the magnetic disk when the magnetic disk is stopped, the magnetic head comes into contact with the surface of the magnetic disk through the projections on the pattern projections formed on the magnetic head. For this reason, the conventional contact between mirror surfaces is eliminated, and the phenomenon that the magnetic head is attracted to the magnetic disk does not occur. Therefore, the failure of the magnetic recording device that has conventionally occurred due to the attraction phenomenon of the magnetic head does not occur.

On the other hand, the first mask pattern is formed on the substrate of the magnetic disk or the coating layer formed on the magnetic head, and then etching is performed to form pattern protrusions, and then the second mask pattern is formed thereon. By forming and then forming the protrusions by etching, a two-step structure having protrusions formed on the pattern protrusions can be obtained. Therefore, by carrying out this method, it is possible to manufacture a magnetic disk and a magnetic head that can exhibit excellent flying characteristics and sliding characteristics.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of a magnetic disk adopting the structure of the present invention. Magnetic disk 1 of this example
Is a disk-shaped substrate made of metal, glass, or resin, which has a magnetic film, a protective film or, if necessary, a plurality of base films coated on the front surface or the back surface. It is used as a recording medium. Further, a magnetic head 2 is pressed against a front surface side or front and back surface sides of the magnetic disk 1 by a spring plate 3 with a predetermined spring pressure. This magnetic head 2
Is connected to a drive device (not shown) that supports the spring plate 3, and the magnetic head 2 moves from a desired position on the inner circumference side of the magnetic disk 1 to an outer circumference side by rotating or moving the spring plate 3 in parallel. It can be moved to a desired position.

As shown in FIG. 2, the magnetic head 2 of this embodiment includes a plate-shaped slider 2a and a core portion 2b and a core portion 2b formed on the rear end side (trailing side) of the slider 2a. With a wound winding coil 2c,
An inclined surface 2d for flying is formed on the bottom surface of the slider 2a on the front end side (leading side).

On at least one of the front surface and the back surface of the magnetic disk 1, a large number of V-shaped pattern projections 5 are formed at predetermined intervals in the moving area of the magnetic head 2 along the circumferential direction of the magnetic disk 1. ing. This pattern protrusion 5
2 is formed by projecting from the surface of the magnetic disk 1 as shown in FIG. 2, and is formed by joining linear air guide portions 5a, 5a in a V shape as shown in FIG. Also,
An air compression portion 5b is formed by a plane triangular space area sandwiched between the air guiding portions 5a, 5a joined in an inclined state.
It is said that.

The height (thickness) of the pattern projection 5 is preferably about 60 nm or more in consideration of the air compression effect and the mean free path of air, but it is as low as a fraction of 60 nm (thin). ) Even if formed, it produces an air compression effect, and is not particularly limited to the above value. In addition, on the front surface or the back surface of the magnetic disk 1, the surface on which the pattern protrusion 5 is formed, that is, the upper surface of the pattern protrusion 5, and
A large number of protrusions 6 are formed on the portions where the pattern protrusions 5 are not formed. The protrusion 6 is formed in a cylindrical shape, and the diameter thereof is formed to be a value of a fraction to a few tenths of the width of the air guide portion 5a of the pattern protrusion 5. The height of these protrusions 6 is 10 to 20 nm.
The degree is preferable, but it goes without saying that it may be formed higher than this. Further, the area occupied by the projections 6 is preferably 0.5% or less with respect to the total area of the pattern projections 5. Although the projection 6 is formed in a cylindrical shape in this embodiment, any shape such as a prismatic shape, a truncated cone shape, or a truncated pyramid shape may be adopted.

Next, the operation of the magnetic disk 1 having the pattern projecting portion 5 configured as described above will be described. The magnetic disk 1 of this embodiment is used for a magnetic storage device of a computer like a normal magnetic disk, and is rotated at a constant speed by a motor (not shown).
Then, the magnetic head 2 is, like a normal magnetic head,
When the magnetic disk 1 is stopped, the magnetic disk 1 comes into contact with the surface of the magnetic disk 1, and the magnetic disk 1 rotates to levitate and to write and read magnetic information as necessary.

When the magnetic disk 1 starts to rotate, the pattern protrusion 5 also moves in the air. Then, the pattern protrusion 5 compresses the air that has entered the air compression portion 5b from both sides by the air guide portions 5a and 5a, so that a high positive pressure region is generated above the pattern protrusion 5.

The innumerable pattern projections 5 formed on the front surface or the back surface of the magnetic disk 1 rotate while forming a positive pressure area above them, respectively, so that a large air flow is generated,
The magnetic head 2 pressed against the magnetic disk 1 is
The lift generated by this air flow makes it easy to levitate and
The state shown in FIG. Here, even in a normal magnetic disk having no pattern formed, an air flow is generated by rotation. However, in the magnetic disk 1 having the pattern projections 5 ... Formed by the air compression effect of the pattern projections 5 at the start of rotation. The positive pressure generated can immediately generate a strong air flow, so that the magnetic head 2 levitates and travels faster than before. Therefore, at the start of rotation of the magnetic disk 1, the time for the magnetic head 2 to contact and rub the magnetic disk 1 is shortened, and the risk of damaging the magnetic disk 1 is reduced.

The bottom surface of the magnetic head 2 (medium facing surface)
Is mirror-finished, and the surface of the magnetic disk 1 is also mirror-finished. However, in the configuration of this embodiment, the projections 6 on the pattern projections 5 come into contact with the bottom surface of the magnetic head 2, so the contact area is small. Since the mirror surfaces are not in contact with each other, the adsorption phenomenon is not caused. Further, at the start of rotation of the magnetic disk 1, the magnetic head 2 starts to fly after sliding while rubbing the protrusions 6 of the magnetic disk 1. Therefore, the projections 6 may be worn to some extent by sliding on the magnetic head 2, but since the projections 6 are columnar,
The contact area with the magnetic head 2 does not change even if it is worn to some extent. Therefore, the effect of the protrusion 6 that reduces the friction of the magnetic head 2 can be exhibited for a long period of time.

FIG. 4 shows another example of the structure of the pattern protrusion 5. In this example, in the air guide portion 5a of the pattern protrusion 5'formed on the magnetic disk 1, the rotating direction of the magnetic disk 1 is changed. The front side 5A is formed thicker than that of the previous embodiment, the rear side 5B in the rotational direction is formed thinner than the front side 5A, and a large number of protrusions 6 are provided. Other configurations are the same as those of the pattern protrusion 5 of the above-mentioned embodiment. By adopting the configuration shown in FIG. 4, the volume of the air compression portion 5b can be increased, and the amount of air compressed by the air guide portions 5a, 5a of the pattern protrusion 5 ′ can be increased. A positive pressure higher than that of the pattern protrusion 5 shown in FIG. 3 can be generated, and the magnetic head 2 can be levitated more quickly.

FIG. 5 shows another structural example of the magnetic disk 1 having the pattern projections 5 and the projections 6 ...
In the magnetic disk 10 of this example, the pattern protrusion 5
This is an example in which the groove portion 11 for assisting air compression is formed on the surface portion of the magnetic disk 10 below the air compression portion 5b. The groove 11 is formed such that the depth of the groove 11 is deep on the lower side of the front side 5A of the magnetic disk 1 in the rotating direction and is shallower on the lower side of the rear side 5B of the magnetic disk 1 in the rotating direction. ing. By adopting the configuration shown in FIG. 5, it is possible to increase the volume of the air compressing portion 5b and increase the amount of air compressed by the air guiding portions 5a, 5a. Therefore, as shown in FIG. 2 and FIG. A positive pressure higher than that of the configuration can be generated, and the magnetic head 2 can be levitated more quickly.

FIG. 6 shows a second example of the structure of the pattern projection according to the present invention. The pattern projection 12 of this example has a structure in which air guides 12a and 12a are connected by a wall 12c. An area that is formed in a letter shape and that is surrounded by the air guiding portions 12a and 12a and the wall portion 12c is an air compressing portion 12b, and a plurality of protrusions 6 are formed on the air guiding portions 12a and 12a. The pattern projections 12 and the projections 6 having this configuration can also achieve the same effects as those of the pattern projections 5 and the projections 6 described above.

FIG. 7 shows a third configuration example of the pattern protrusion according to the present invention. The pattern protrusion 13 of this example is constituted by connecting air guiding portions 13a and 13a in an X shape.
An air compression portion 13b is formed between the end of the air guide portion 13a and the end of the other air guide portion 13a, and the air guide portion 13 is formed.
A plurality of protrusions 6 ... Are formed on a and 13a. With the pattern protrusions 13 and the protrusions 6 ... With this configuration, the same effects as those of the pattern protrusions 5 and the protrusions 6 described above can be obtained.

FIG. 8 shows a fourth configuration example of the pattern protrusion according to the present invention. The pattern protrusion 14 of this example has short air guiding portions 14a, 1a at both ends of a horizontally long wall portion 14c.
4a extends at a right angle and a plurality of protrusions 6 are formed. With the pattern protrusion 14 having this structure, the same effects as those of the pattern protrusion 5 and the protrusions 6 described above can be obtained.

By the way, the magnetic disk 1 includes a single-sided type in which a magnetic layer is formed only on the front surface and a double-sided type in which a magnetic layer is formed on both the front and back surfaces. Pattern protrusion 5 and protrusion 6
In the case of the double-sided type, the pattern projections 5 and the projections 6 are formed on both front and back surfaces.

Next, an example of a method of manufacturing the magnetic disk 1 configured as described above will be described with reference to FIG. In this example, a magnetic disk having the most general laminated structure will be described as an example. In order to manufacture the magnetic disk 1, a disk-shaped material substrate 20 made of Al, Al alloy, glass or the like is prepared, and the material substrate 20 is chamfered or surface-treated and then the surface thereof is made of Ni-P or the like. A coating film 21 is formed by plating or the like as shown in FIG. 9A to obtain a substrate 19.

Next, the surface of the coating film 21 is polished at the stage shown in FIG. 9 (b). Then, after this step, the surface of the coating film 21 is covered with a mask capable of exposing a portion other than the pattern protrusions described above, and the coating film 21 is formed on the coating film 21 by using a photolithography technique such as ion milling. A large number of pattern protrusions and protrusions are formed.

Here, an example of a method for forming the pattern protrusions and protrusions using the photolithography technique will be described in detail below with reference to FIGS. 10 and 11. First, the pattern protrusion 5 is formed by performing the process described below based on FIG. To this end, the substrate 19 shown in FIG.
10B, a first photoresist 40 is applied to the surface thereof, and a first photomask 41 is applied to the surface of the first photoresist 40 as shown in FIG. Irradiate. The first photomask 41 used here is
Considering the surface of the magnetic disk 1 described above, the ultraviolet ray passing portion 41a is formed so that the ultraviolet rays can pass through the same area as the area excluding the pattern protrusions 5, and the other portion is the ultraviolet light shielding portion 41b. Is formed.

By covering the first photomask 41 and irradiating it with ultraviolet rays, the solubility changing portion 40a is formed in the first photoresist 40 as shown in FIG. 10C. The solubility changing portion 40a is formed by the pattern protrusion 5
It has the same planar shape as the region of the part excluding. Next, when the first photoresist 40 is developed, the first mask pattern 42 is formed as shown in FIG. 10D, and thus the surface portion of the substrate 19 in this state is shown in FIG. Etching on the first mask pattern 4
If 2 is removed, a substrate 18 having a plurality of pattern protrusions 5 formed on its surface can be obtained.

Next, the steps described below with reference to FIG. 11 are performed on the substrate 18 to form the protrusions 6. First,
A second photoresist 43 is applied to the surface of the substrate 18 as shown in FIG. 11A, and a second photomask 45 is covered as shown in FIG. Irradiate. Second photomask 4 used here
In consideration of the surface of the magnetic disk 1 described above, the ultraviolet ray passing portion 45a is formed so that the ultraviolet ray can pass through the same area as the area other than the area where the protrusion 6 is formed, and the other portions are The ultraviolet light shielding portion 45b is formed.

After covering the second photomask 45,
Ultraviolet rays are radiated from above to form a solubility changing portion 43a on the second photoresist 43 as shown in FIG. The solubility changing portion 43a has the same planar shape as the area of the portion excluding the protrusion 6. Next, when a part of the second photoresist 43 is developed, a second mask pattern 46 is formed as shown in FIG. 11C, and in this state, the surface portion of the substrate 18 is exposed as shown in FIG. 11D. By engraving by etching and then removing the second mask pattern 46 as shown in FIG. 5, a substrate 18 having pattern projections and projections formed on the surface can be obtained.

Next, as shown in FIG. 9C, a process for forming the texture ring 22 is performed, and thereafter, a film forming means such as sputtering is used to form Cr as shown in FIG. 9D.
A base film 23 made of, for example, is coated. In this step, the step of forming the texture ring 22 may be omitted.

Next, Co-Ni-C is formed on the base film 23.
The magnetic film 24 made of an r film or the like is covered by a film forming means such as sputtering as shown in FIG. 9E, and a protective film 25 made of carbon or the like is formed by a film forming means such as sputtering.
The magnetic disk 1 is completed by coating as shown in (f) and further forming a lubricating film 26 made of a fluorine-based lubricant by a method such as a dip coating method. In the manufacturing method, after the polishing process shown in FIG.
0 and the steps described with reference to FIG. 11 are performed to form pattern protrusions and protrusions, each laminated film formed on them is sequentially coated on them, and the shapes of the pattern protrusions and protrusions are faithfully reproduced. As a result of being stacked while being copied, a large number of pattern protrusions 5 and protrusions 6 are formed on the surface of the magnetic disk 1. The base film 23, the magnetic film 24, and the protective film 2 formed here
5 and the lubricating film 26 have a thickness of several hundreds to several hundreds of liters, the pattern protrusions and protrusions formed on the substrate 18 and having a thickness of several tens nm are faithfully copied. By manufacturing the magnetic disk 1 as described above, it is possible to obtain the magnetic disk 1 having a large number of pattern projections 5 and projections 6.

By the way, in the above-mentioned embodiment, the pattern protrusions and the protrusions are formed in the course of stacking a large number of films, and the magnetic film 24 and the protective film 25 are coated thereon to transfer the pattern protrusions and the protrusions. Although the pattern protrusions 5 and the protrusions 6 are formed on the surface of the magnetic disk 1, the step of forming the pattern protrusions and protrusions is performed after the formation of the protective film 25, and the pattern protrusions and protrusions are formed on the upper surface of the protective film 25. May be. In this case, the protective film 25 may be formed to be sufficiently thick and a stamper having a large number of pattern projections or projections formed thereon may be pressed to transfer a large number of pattern projections or projections at one time. When the protective film 25 is a hard film, a step of forming a new intermediate film is incorporated before the step of forming the protective film 25, and a large number of patterns are formed on this intermediate film by using a stamper. It is also possible to cover with the protective film 25.

Next, the relationship between the arrangement state and the size of the pattern protrusions formed on the magnetic disk will be described. FIG. 12 shows an example of a pattern arranged along the rotation direction of the magnetic disk. In this example, the pattern protrusion 3
0 to 34 are arranged, but the patterns on the inner peripheral side of the outer peripheral side of the magnetic disk are formed so as to become successively smaller and more densely arranged.

In the structure of this example, the number of revolutions of the magnetic disk is constant, and a difference in peripheral speed occurs between the inner peripheral side and the outer peripheral side.
This is a configuration for coping with the phenomenon that the flying height of the magnetic head varies. That is, in a magnetic disk without a normal pattern protrusion, the airflow generated at the outer peripheral portion with a high peripheral velocity is strong, so the flying height of the magnetic head is large, and the airflow generated at the inner peripheral portion with a low peripheral velocity is small. The flying height of the head is reduced. On the other hand, in the configuration shown in FIG. 12, the patterns 30 are small and densely arranged so that a stronger airflow can be generated in the inner peripheral portion having a low peripheral velocity, and the pattern 34 is large in the outer peripheral portion. And they are sparsely arranged. By adopting such a configuration, in the magnetic disk,
The flying height of the magnetic head can be made uniform on the inner peripheral side and the outer peripheral side by reducing the difference in the air flow generated on the inner peripheral side where the peripheral speed is low and the outer peripheral side where the peripheral speed is high.

13 to 15 show a first embodiment in which the present invention is applied to a monolithic three-rail type magnetic head. The magnetic head 50 of this example includes a slider 52 having three rail portions 51 formed therein.
A core portion 53 is joined to the center of the rear end portion of the rear portion.
An inclined surface 5 for assisting levitation traveling is provided at the tip of each rail portion 51.
5 is formed. In the magnetic head 50 of this example, the right end in the figure is the leading side, that is, the rear side in the rotational direction of the magnetic disk, and the left rear end in the figure is the trailing side, that is, the front side in the rotational direction of the magnetic disk. ..

In the magnetic head 50 of this example, a V-shaped pattern protrusion 56 is formed on the rail portion 51. The pattern projection 56 is formed by connecting two air guides 56a, and an air compression part 56b formed between them is directed to the rear side in the rotation direction of the magnetic disk. A plurality of protrusions 6 are formed on the bottom surface (surface on the magnetic disk side) of the pattern protrusion 56.

The magnetic head 50 of this embodiment is used in a conventional magnetic disk having no pattern protrusion in the same manner as the conventional one, or in the magnetic disk 1 having the structure described above. When used for any of the above magnetic disks, the pattern projections 56 generate the airflow generated by the rotation of the magnetic disks.
Since it can be compressed by the air compressor 56b and converted into lift force, it can levitate faster than the conventional magnetic head, thereby stabilizing the levitating traveling of the magnetic head 50 and destroying the surface of the magnetic disk. It is possible to reduce the risk of. Further, since the pattern projections 56 and the projections 6 are formed on the rail portion 51, the magnetic head 50 comes into contact with the magnetic disk through the projections 6 of the pattern projections 56 when the magnetic disk is stopped. Then, unlike the case where the mirror surface of the magnetic disk and the mirror surface of the magnetic head are in contact with each other, the phenomenon of attraction between the mirror surfaces does not occur, so that the problem that the magnetic head does not run due to the attraction phenomenon does not occur.

Next, a method of forming the pattern protrusions 56 and the protrusions 6 on the magnetic head 50 having the above structure will be described. Since the slider 52 of the magnetic head 50 is made of a magnetic material such as ferrite in this example, a coating layer made of glass or a non-magnetic material forming the substrate of the magnetic disk 2 is formed on the bottom surface of the slider 52. .. Next, the coating layer is subjected to a method similar to the method described with reference to FIGS. 10 and 11, and the pattern protrusion 56 is formed by photolithography.
By forming the projections 6 ... And the magnetic head 50 having the pattern projections 56 and the projections 6 on the rail portions 51, 51 can be manufactured.

[0047]

[Test example]

(Test Example 1) FIG. 16 shows a case where a running test was conducted using the magnetic disk and the magnetic head having the configurations shown in FIGS.
AE that appears at the beginning of the rotation of the magnetic disk
(Acoustic emission) It shows the result of measuring the output. The AE output means a minute electric signal component obtained by piezoelectrically converting an elastic wave emitted from the magnetic head when the magnetic head slides while contacting the surface of the magnetic disk at the start of rotation of the magnetic disk. There is.
In this test, a monolithic three-rail type magnetic head was used, and a 3.5-inch size magnetic disk was rotated at a rotation speed of 3600 rpm. In addition, the surface of the magnetic disk is V-shaped, its thickness is 60 nm, and the total length is 0.4.
6 mm, maximum width of air compression part 0.07 mm, pitch of pattern guide with width of air guide part set to 5 μm 0.1 m
A large number of projections each having a height of 20 nm and a diameter of 3 nm were formed on the entire surface of the magnetic disk. As is clear from the results shown in FIG. 16, the magnetic head having a large number of protrusions according to the present invention has a shorter time during which the AE output is generated than the conventional magnetic head. This means that the magnetic head according to the present invention levitates faster than the conventional magnetic head, which causes the AE output to disappear earlier. From the above, it has been clarified that the structure of the present invention can accelerate the floating of the magnetic head.

(Test Example 2) Next, a test was conducted to find out how much the friction coefficient changes when the magnetic head repeatedly contacts and separates from the magnetic disk. The result is shown in FIG. In this test, the same magnetic head and magnetic disk as those used in Test Example 1 were used. FIG. 17 shows changes in the value of the friction coefficient when the contact state of the magnetic head with respect to the magnetic disk and the flying running state are repeatedly performed 20000 times or more. The friction coefficient of this test example is the maximum friction force at the time of startup or steady sliding when the magnetic head and the magnetic disk are left in contact with each other for 1 minute after the predetermined CSS times and then the magnetic disk is rotated at 1 rpm. I asked more. The frictional force was measured by a strain gauge type load cell to which a magnetic head was connected. As is clear from FIG. 17, the magnetic disk according to the present invention has a smaller friction coefficient than the conventional magnetic disk.

[0049]

As described above, according to the present invention, since a plurality of pattern projections having the air compression portion facing the front side in the rotation direction of the magnetic disk are formed on the surface of the magnetic disk,
When the magnetic disk is rotated, the air compression portion of each pattern projection acts to generate a positive pressure area on the surface of the magnetic disk, and an air flow resulting from this can be generated on the surface of the magnetic disk. Therefore, by applying this air flow to the magnetic head, the magnetic head can be quickly levitated at the start of rotation of the magnetic disk. Although an air flow is generated by rotation even in a normal magnetic disk that does not have a pattern protrusion, in a magnetic disk that has a pattern protrusion, a positive pressure generated by the air compression effect of the pattern protrusion at the start of rotation. As a result, a strong air flow can be generated immediately, so that the magnetic head floats faster than the conventional magnetic disk. Therefore, the time for the magnetic head to contact and rub against the magnetic disk at the start of rotation of the magnetic disk is shortened, and there is no risk of damaging the magnetic disk.

When the magnetic head is in contact with the magnetic disk when the magnetic disk is stopped, the magnetic head is brought into contact with the magnetic disk through the projections on the pattern projections formed on the magnetic disk. You can Then, the conventional contact between the mirror surfaces is eliminated, and the contact area is reduced, so that the phenomenon that the magnetic head is attracted to the magnetic disk does not occur. Therefore, the failure of the magnetic recording device that may occur in the past due to the magnetic head attraction phenomenon does not occur.

On the other hand, in the magnetic head on which the magnetic disk side surface is provided with the pattern projection having the air compression portion facing the rear side in the rotation direction of the magnetic disk, the pattern projection is formed when the magnetic disk is rotated. The positive pressure generated by the action of the air compression unit acts on the magnetic head. Therefore, the magnetic head can receive a strong lift force by the action of this positive pressure, and the magnetic head floats faster than the conventional magnetic head. Further, when the pattern protrusion of the magnetic disk comes into contact with the magnetic disk, the contact area is smaller than that of the conventional mirror finish, so that the magnetic head is not likely to be attracted to the magnetic disk. Therefore, the time for the magnetic head to contact and rub against the magnetic disk at the start of rotation of the magnetic disk is shortened, and the risk of damage to the magnetic disk can be reduced.

In addition, a first mask pattern is formed on a substrate of a magnetic disk or a coating layer formed on a magnetic head, and then etching is performed to form a pattern protrusion, and then a second mask pattern is formed thereon. By forming and then forming projections on the magnetic disk, or on the surface of the magnetic head on the magnetic disk side,
It is possible to manufacture a two-step structure having a structure in which protrusions are formed on the pattern protrusions. As described above, a magnetic disk and a magnetic head having the excellent floating characteristics and sliding characteristics of the magnetic head are manufactured. can do.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a magnetic disk according to the present invention and an arrangement state of magnetic heads.

FIG. 2 is a side view of an arrangement state of a magnetic disk and a magnetic head shown in FIG.

FIG. 3 is a perspective view showing an example of a pattern formed on the magnetic disk shown in FIG.

4 is a cross-sectional view showing another example of the pattern shown in FIG.

5 is a cross-sectional view showing another example of the pattern shown in FIG.

FIG. 6 is a perspective view showing a second example of the pattern according to the present invention.

FIG. 7 is a perspective view showing a third example of the pattern according to the present invention.

FIG. 8 is a perspective view showing a fourth example of the pattern according to the present invention.

FIG. 9 is an explanatory diagram for explaining a method of manufacturing a magnetic disk by carrying out the method of the present invention.

FIG. 10 is an explanatory diagram for explaining the details of the step of forming a pattern protrusion in the method described with reference to FIG.

FIG. 11 is an explanatory diagram for explaining details of a step of forming a protrusion in the method described with reference to FIG. 9.

FIG. 12 is an enlarged perspective view showing an example of an array state of patterns formed on a magnetic disk.

FIG. 13 is a perspective view showing a magnetic head having a pattern according to the present invention.

FIG. 14 is a side view of the magnetic head shown in FIG.

FIG. 15 is a bottom view of the magnetic head shown in FIG.

FIG. 16 is a diagram showing AE output characteristics when a magnetic head was subjected to a running test on a magnetic disk according to the present invention.

FIG. 17 is a diagram showing a friction coefficient when a magnetic head is run on a magnetic disk according to the present invention.

[Explanation of symbols]

1 magnetic disk, 2 magnetic head, 2a slider, 5, 5'pattern protrusion, 12, 13,
14 pattern protrusions, 6 protrusions,

Claims (4)

[Claims] 1. A magnetic disk in which information is read from and written to by a magnetic head and is rotationally driven, and a pattern protrusion having an air compression portion facing the front side in the rotation direction of the magnetic disk on at least one of the front surface and the back surface of the magnetic disk. A magnetic disk, wherein a plurality of portions are formed, and a plurality of protrusions smaller than the pattern protrusions are formed on the surface of the pattern protrusions. 2. A magnetic disk in which information is read and written by a magnetic head and is rotationally driven, and a pattern protrusion is provided on at least one of a front surface and a back surface of the magnetic disk, the air compression section facing forward in a rotational direction of the magnetic disk. In a method of manufacturing a magnetic disk in which a plurality of portions are formed and a plurality of projections smaller than the pattern projections are formed on the surface of the pattern projections, a first mask pattern is formed on a substrate of the magnetic disk. A part of the substrate is selectively etched along the first mask pattern to form a pattern protrusion on the front surface or the back surface of the substrate, and a second mask pattern is further formed on the substrate on which the pattern protrusion is formed. Then, a part of the pattern protrusion is selectively etched along the second mask pattern to form a protrusion on the surface of the pattern protrusion. Method of manufacturing a magnetic disk, wherein a plurality of formation. 3. A magnetic head that floats on a rotating magnetic disk and contacts the magnetic disk in a stopped state. The magnetic head faces the magnetic disk side surface of the magnetic head, and faces rearward in the rotating direction of the magnetic disk. A magnetic head comprising: a pattern protrusion having an air compression portion; and a plurality of protrusions smaller than the pattern protrusion formed on a surface of the pattern protrusion. 4. A magnetic head that floats on a rotating magnetic disk and contacts the magnetic disk in a stopped state, wherein the surface of the magnetic head on the magnetic disk side is the rear side in the rotating direction of the magnetic disk. In the method of manufacturing a magnetic head in which a pattern protrusion having an air compressing portion facing toward is formed, and a plurality of protrusions smaller than the pattern protrusion are formed on the surface of the pattern protrusion, A coating layer is formed on the surface, and a first mask pattern is formed on the coating layer.
Part of the coating layer is selectively etched along the mask pattern of 1 to form a pattern protrusion on the surface of the coating layer, and a second mask pattern is further formed on the coating layer on which the pattern protrusion is formed. A method of manufacturing a magnetic head, characterized in that a part of the pattern projection is selectively etched along the second mask pattern to form a plurality of projections on the surface of the pattern projection.